mus: Let clients set the cursor of their window.

components/mus/ws/display_manager.h

Index: components/mus/ws/display_manager.h
diff --git a/components/mus/ws/display_manager.h b/components/mus/ws/display_manager.h
index c8596b106ec7a9cff4fed6f0a33a46fe19d809d2..3705d96defa792c9f30065903bfc7f221bb85e13 100644
--- a/components/mus/ws/display_manager.h
+++ b/components/mus/ws/display_manager.h
@@ -32,6 +32,7 @@ class ApplicationImpl;
 }  // namespace mojo
 
 namespace ui {
+class CursorLoader;
 class PlatformWindow;
 struct TextInputState;
 }  // namespace ui
@@ -68,6 +69,8 @@ class DisplayManager {
 
   virtual void SetTitle(const base::string16& title) = 0;
 
+  virtual void SetCursorById(int32_t cursor) = 0;
+
   virtual const mojom::ViewportMetrics& GetViewportMetrics() = 0;
 
   virtual void UpdateTextInputState(const ui::TextInputState& state) = 0;
@@ -103,6 +106,7 @@ class DefaultDisplayManager : public DisplayManager,
                      const gfx::Rect& bounds) override;
   void SetViewportSize(const gfx::Size& size) override;
   void SetTitle(const base::string16& title) override;
+  void SetCursorById(int32_t cursor) override;
   const mojom::ViewportMetrics& GetViewportMetrics() override;
   void UpdateTextInputState(const ui::TextInputState& state) override;
   void SetImeVisibility(bool visible) override;
@@ -149,6 +153,10 @@ class DefaultDisplayManager : public DisplayManager,
   scoped_ptr<TopLevelDisplayClient> top_level_display_client_;
   scoped_ptr<ui::PlatformWindow> platform_window_;
 
+#if !defined(OS_ANDROID)
+  scoped_ptr<ui::CursorLoader> cursor_loader_;
+#endif
+
   base::WeakPtrFactory<DefaultDisplayManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultDisplayManager);